Such a safety helmet, that in the motorcycle field goes with the traditional integral helmets, that are provided with a chin guard integral to the shell, and the so-called “jet” helmets, without the chin guard, usually provides a reversible mechanism for fixing the chin guard in a position protective the lower portion of the user face, that is in a pulled down position, that has to permanently assure such a position maintaining in case of impact too.
These mechanisms for reversibly fixing the chin guard in the pulled down position, that in a simple embodiment thereof may comprise, for example, elastic hooks pivoted to the chin guard which, thanks to the operating of specific tie rods or struts connected with such hooks and operated by a manual control, are driven by the user in engagement and/or disengagement positions with corresponding strikers provided on the shell of the helmet itself, usually do not provide any stable fixing of the chin guard, when this latter is in its raised position.
For such reasons it is therefore recommended that, with such helmets, the user has to utilize the helmet operatively with the chin guard in a pulled down position protective the face of the user itself, so to obtain a helmet comparable with the so-called integral helmets.
However, in some cases in practice, it may be useful or necessary maintaining the chin guard in a raised position, so to obtain a helmet comparable with a “jet” type helmet.
Concerning this, it is known art to provide such a helmet type, with a raisable chin guard, not only with the aforesaid fixing mechanism in a pulled down position, but with a device for reversible locking, that is user controlled, the chin guard in its raised position as well.
Devices for reversible locking the chin guard in the raised position may comprise, in a simplified embodiment thereof, an elastic stop that, placed on the shell so that to engage with the chin guard only when this latter is in proximity of its raising position, in normal conditions is opposing to the chin guard rotation, unless the user would not exercise on the chin guard itself a force sufficient for temporarily deforming such an elastic stop and thereby allowing the chin guard rotation resumption.
For example, the U.S. Pat. No. 6,249,918 (LACROIX) provides that such a device for locking the chin guard in a raised position comprises a circular guide groove, integral with the shell, provided in the interior with an elastic projection transversally and partially protruding into such a guide groove. The chin guard is, in its turn, provided with a projection, or follower, that is slidingly coupled inside the guide groove such that, during its raising or pulling down, such a follower will move within the circular groove integral with the shell. The elastic projection is placed inside the groove so that, when the chin guard is in proximity of its position of highest raising, it would interfere with the aforesaid follower, thereby acting as an elastically yielding stop.
Only when the user exercises a force that is able to temporarily deform such an elastic projection, the follower, integral with the chin guard, will be able to go past the elastic projection and reach the limit stop defined by the guide groove, corresponding to the position of highest raising of the chin guard. In absence of countering forces, when the follower will arrive at such a limit-stop position, the elastic projection will be able to hold the chin guard in its position of highest raising.
In the same way, the European Patent Application EP-A-0895726 in the name of LOCATELLI, describes a safety helmet provided with a raisable chin guard, comprising an elastic projection, integral with an inner wall of the chin guard, that could engage into a complementary seat obtained on the shell, when the chin guard is in proximity of its raised position. The engagement or disengagement of the elastic projection into the complementary seat takes place only if it is exercised by the user a force sufficient to allow the elastic collapse of the aforesaid projection.
Such type of devices, substantially based on the strength opposed by an elastically deformable element integral to the shell, against a rigid element integral to the chin guard, or vice versa, although simply structured and realized, nevertheless reveal poor effectiveness in maintaining the chin guard in its raised position, because it is sufficient the exercise of an accidental force against the chin guard, although not so excessive, to unlock this latter from its raised position and cause an undesirable pulling down.
In fact, as it will be evident to a person skilled in the art, it is not possible to excessively stiffen the elastically deformable element, because if this latter is too much rigid, although it prevents the accidentally exercised forces from causing the sudden pulling down of the chin guard, once this latter is in its raised position and held by the aforesaid reversible locking device, it will be difficult for the user to overcome the strength provided by the same elastically deformable element during the raising/pulling down step of the chin guard, and, in case of pulling down, the stiffness of the elastically deformable element may cause, if the force exercised by the user is sufficient, an undesirable rotation downward of the helmet (in this case integral with the chin guard), or a sudden undesirable pulling down of the chin guard may occur.
In the International Application WO-A-2006045912 in the name of SHARK a different, user controlled, device is described for reversibly locking the chin guard in its raised position, nay turned over, in helmets having a turning over chin guard.
The locking device described in the SHARK patent application provides that the chin guard is connected to the shell by a rotatable and sliding constrain (that is a slider) and that the motion and the chin guard position, during the raising and pulling down operations, are defined by the engagement of a follower, integral to the chin guard, into a guide groove, obtained on the shell.
The shape of the guide groove is such that the chin guard could reach an extremely rearward position on the shell relatively to the front opening of the shell itself. The guide groove further provides some limit-stop inlets for the follower, preventing the user from moving the chin guard from the corresponding limit stop without the user itself exercises a complicated roto-translation of the same chin guard.
However such a device, although simple and effective for locking the chin guard in the raised position, obliges the user to exercise on the chin guard forces in unusual and difficult to execute direction and ways. Further such a device does not allow to raise temporarily the chin guard, without this latter being locked in its raised position (turned over).
It is an object of the present invention to carry out a safety helmet with a turning over chin guard of the type comprising a device for locking the chin guard in a raised position not presenting the drawbacks of the prior known art, above reported.
It is further an object of the present invention to carry out a safety helmet with a turning over chin guard comprising a device for locking the chin guard in a raised position, allowing to effectively lock the chin guard in a raised position only when the user wants to, and in the meanwhile being easy to operate by the user.
A further object of the present invention is to provide a safety helmet with a turning over chin guard comprising a device for locking the chin guard in a raised position, allowing, at user discretion, both a stable locking and a yielding locking, that is of the type wherein only one elastic or friction countering element, or an unstable rest is opposing to the chin guard motion, that is easy and practical to plan and carry out.